In my ignorance, of the size of the tank when ordering my GC 180, I told him 2 MH would be used.
Guess what, I was wrong and/or stupid. The center brace is directly below one of my 3 MH's. While light gets through, it is much less than the free light areas available to the other 2 MH's.
Go with 2 braces allowing free access to all lights.
What I have found though is some corals like being under the reduced light area, though available knowledge say's they should'nt
JMTCW
Rick